Method for forming a fuel tank assembly

ABSTRACT

A heat shield retainer and method for mounting a heat shield onto a polymeric fuel tank. The heat shield retainer comprises a nut and bolt combination and a retainer body. The retainer body has bulbous pegs located on a first side thereof for engaging within corresponding sockets located within a fuel tank to secure the retainer body to the fuel tank. The retainer body further includes a releasable channel located on a second side thereof for releasably connecting the nut and bolt thereto. One or more retainers of the present invention may be employed to mount a heat shield onto a polymeric fuel tank. After a polymeric tank has been formed, and before it has cooled, the respective pegs of each heat shield retainer are inserted into corresponding sockets located within the fuel tank. As the tank cools, the polymeric material of the tank defining the sockets contracts about the pegs. As a result, after the tank cools, the pegs are locked within the sockets, and hence to the fuel tank.

This is a division of application Ser. No. 07/516,002 filed Apr. 16,1990, now U.S. Pat. No. 5,067,575.

BACKGROUND OF THE INVENTION

The present invention generally relates to a retainer for connecting twomembers together and, more particularly, to a heat shield retainer forconnecting a heat shield to a fuel tank.

It is known in the prior art to use fuel tanks made from polymericmaterials, such as polyethylene, in motor vehicles. Such fuel tanks areadvantageous because they resist corrosion and can be easily formedhaving various shapes and sizes, thus permitting flexibility in theirdesign. Further, since polymeric fuel tanks are light weight, they makethe vehicles in which they are employed more fuel efficient andeconomical to operate.

Heat shields have been in used in the past in combination with polymericfuel tanks. The heat shields serve to reflect a harmful portion of theheat emitted from the exhaust system away from the fuel tanks. The heatshields are normally mounted to the fuel tanks a spaced distancetherefrom by heat shield retainers. Air contained within the spaceddistance between the heat shield and the fuel tank acts as an insulatorfor the fuel tank.

Heat shield retainers for mounting a heat shield to a polymeric fueltank have, in the past, been welded onto the polymeric fuel tanks inorder to be connected thereto. Welding heat shield retainers onto fueltanks, however, has been found to be inefficient and tedious. This isbecause, in order to connect a heat shield retainer to a polymeric fueltank, an operator must proceed through a time consuming welding process.

Accordingly, a need exists for an improved heat shield retainer wherebya simplified method may be employed for connecting the same to a plasticfuel tank.

SUMMARY OF THE INVENTION

This need is met by the present invention which employs a heat shieldretainer having pegs thereon in order to mount a heat shield onto a fueltank. The heat shield retainer is connected to the fuel tank by the pegswhich are lockingly engaged within sockets in the fuel tank. Thus, theheat shield retainer of the present invention may be secured to a fueltank without being welded thereto.

The heat shield retainer of the present invention comprises a nut andbolt combination and a retainer body. The retainer body has pegs locatedon a first side thereof for engaging within corresponding sockets formedinto the outer surface of a fuel tank to secure the retainer body to thefuel tank. The retainer body further includes a releasable channellocated on a second side thereof for releasably connecting the nut andbolt thereto.

One or more retainers of the present invention may be employed to mounta heat shield onto a polymeric fuel tank. After a polymeric tank hasbeen formed, and before it has cooled, the respective pegs of each heatshield retainer are inserted into corresponding sockets formed in theouter surface of the fuel tank. As the tank cools, the polymericmaterial defining the sockets contracts about the pegs. As a result,after the tank cools, the pegs are locked within the sockets, and henceto the fuel tank.

In accordance with one aspect of the present invention, a fuel tank/heatshield assembly comprises a fuel tank, a heat shield for shielding thefuel tank, and retainer means for mounting the heat shield to the fueltank. The retainer means includes a retainer body having a first sideand a second side, with peg fastening means located on the first side ofthe retainer body for securing the retainer body to the fuel tank.Attachment means are located on the second side of the retainer body forattaching the heat shield to the retainer body. The fuel tank includessocket means for receiving and lockingly engaging the peg fasteningmeans therein to secure the retainer body to the fuel tank. The retainerbody and the peg fastening means may be integrally formed as a singleunit from a polymeric material. The peg fastening means on the retainerbody may comprise one or more bulbous pegs received by the socket means.

The retainer body preferably includes a releasable channel means on thesecond side thereof for releasably connecting the attachment means tothe retainer body. The attachment means may comprises a bolt and nutcombination which is releasably connected to the second side of theretainer body by engagement with the channel means. The bolt comprises amain body section having a head thereon and the releasable channel meansreceives the head and a portion of the main body section of the bolt.The releasable channel means includes a recess defined by a wall in theretainer body. A portion of the wall has an arcuate shape defining asubstantially semicircular opening of substantially the same diameter asthe main body section of the bolt. The wall further has rounded surfacesspaced apart a distance slightly narrower than the main body section ofthe bolt to form a constriction at the entrance of the semicircularopening to releasably capture the main body section of the bolt.

The heat shield protects the fuel tank from a harmful amount of heatgenerated by a motor vehicle by reflecting heat which would otherwise beapplied to the tank. The heat shield is mounted to the fuel tank aspaced distance therefrom. The distance is defined by the retainer meansand permits air contained therein to act as an insulator for the fueltank. The heat shield is preferably made from a metallic material.

In accordance with another aspect of the present invention, a fueltank/heat shield assembly for a motor vehicle comprises a fuel tank, aheat shield for shielding the fuel tank, and retainer means for mountingthe heat shield to the fuel tank. The retainer means includes a retainerbody having a first side and a second side. Fastener means are locatedon the first side of the retainer body for connecting the retainer bodyto the fuel tank. A bolt and nut are releasably connected to theretainer body on the second side thereof for releasably connecting theheat shield to the fuel tank. Releasable channel means are located onthe second side of the retainer body for releasably connecting the boltand nut to the retainer body.

The bolt comprises a main body section having a head thereon and thereleasable channel means receives the head and a portion of the mainbody section of the bolt. The releasable channel means includes a recessdefined by a wall in the retainer body. A portion of the wall has anarcuate shape defining a substantially semicircular opening ofsubstantially the same diameter as the main body section of the bolt.The wall further has rounded surfaces spaced apart a distance slightlynarrower than the main body section of the bolt to form a constrictionat the entrance of the semicircular opening to releasably capture themain body section of the bolt. The fastener means may comprise one ormore bulbous pegs capable of fitting into the same number of sockets inthe fuel tank.

In accordance with a further aspect of the present invention, a retainerfor connecting a heat shield to a fuel tank comprises a retainer bodyhaving a first side and a second side. Fastener means are located on thefirst side of the retainer body for connecting the retainer body to afuel tank and a bolt and nut are releasably connected to the retainerbody on the second side thereof for releasably connecting a heat shieldto the fuel tank. Releasable channel means located on the second side ofthe retainer body provide for releasably connecting the bolt and nut tothe retainer body. The bolt comprises a main body section having a headthereon and the releasable channel means receives the head and a portionof the main body section of the bolt. The releasable channel meansincludes a recess defined by a wall in the retainer body. A portion ofthe wall has an arcuate shape defining a substantially semicircularopening of substantially the same diameter as the main body section ofthe bolt. The wall further has rounded surfaces spaced apart a distanceslightly narrower than the main body section of the bolt to form aconstriction at the entrance of the semicircular opening to releasablycapture the main body section of the bolt. The fastener means maycomprise one or more bulbous pegs capable of fitting into the samenumber of sockets in the fuel tank.

In accordance with still another aspect of the present invention, amethod for forming a fuel tank/heat shield assembly comprises the stepsof: forming a fuel tank having at least one socket therein from heatedpolymeric material; providing a heat shield; providing retainer meansfor connecting the heat shield to the fuel tank, the retainer meansincluding a retainer body having peg fastening means on a first sidethereon for connecting the retainer body to the fuel tank; connectingthe retainer body to the fuel tank by inserting the peg fastening meansinto the at least one socket in the fuel tank after the tank has beenformed and before the tank has cooled in order to permit the socketmeans to contract about the peg fastening means as the tank cools; and,attaching the heat shield to the retainer body.

The retainer means further includes a channel located on a second sideof the retainer body and a nut and bolt combination. The step ofattaching the heat shield to the retainer body comprises the steps of:snap-fitting the bolt in the channel located in the retainer body,placing the heat shield on the retainer body and fastening the heatshield onto the retainer body by threadedly engaging and tightening thenut on the bolt.

According to preferred embodiments of the present invention, it is anobject to provide an improved heat shield retainer whereby a simplifiedmethod may be employed for connecting the same to a plastic fuel tank.This and other objects and advantages of the present invention will beapparent from the following description, the accompanying and theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a fuel tank having a heatshield mounted thereto in accordance with the method and apparatus ofthe present invention;

FIG. 2 is a frontal view of a heat shield retainer of the presentinvention;

FIG. 3 is a cross-sectional view of the heat shield retainer of FIG. 2taken along section line 3--3;

FIG. 4 is a side view of the nut and bolt combination of the heat shieldretainer of FIG. 2; and

FIG. 5 is a perspective view of the retainer body of the heat shieldretainer of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, the retainer 10 of the present invention isschematically shown at three locations about a fuel tank 40 for mountinga heat shield 60 to the fuel tank 40. The fuel tank 40 is preferablymade from a polymeric material, such as polyethylene. The heat shield 60is employed to protect the polymeric fuel tank 40 from harmful amountsof heat generated by an exhaust system on a motor vehicle (not shown).The heat shield 60 is preferably made from a metallic material, such asaluminized steel, so that it may reflect a harmful portion of the heatemitted from the exhaust system away from the fuel tank 40.

The heat shield 60 is mounted a spaced distance defined by the retainers10 from the fuel tank 40. The air contained within the spaced distancebetween the heat shield 60 and the fuel tank 40 acts as an insulator forthe fuel tank 40.

The retainer 10, as best shown in FIGS. 2 and 3, comprises attachmentmeans 50 and a retainer body 12 which releasably receives the attachmentmeans 50. The attachment means comprises a bolt 52 in combination with anut 54. The bolt 52 includes a main body section 56 integrally formedwith a substantially square-shaped base or head 58. The main bodysection 56 is externally threaded in order that the nut 54 may bethreadedly engaged thereon.

The retainer body 12 is preferably formed from a polymeric material,such as polyethylene. The retainer body 12, as best shown in FIG. 5, hasa generally rectangular shape having a lower first side 14, an uppersecond side 16, a front face 18 and a rear face 20. Bishops or bulbouspegs 21 are located on the first side 14 thereof for connecting theretainer body 12 onto the fuel tank 40. The bulbous pegs 21 are receivedwithin corresponding sockets 43 formed into the outer surface of thefuel tank 40, as shown in FIG. 2. The retainer body 12 further includesa releasable channel 22 generally located on the second side 16 thereof.A lower open portion 24 of the channel 22 extends through the retainerbody 12, between the front face 18 and the rear face 20. The head 58 ofthe bolt 52 is received within the lower open portion 24 of the channel22.

The channel 22 further includes an upper recess 26, as best shown inFIG. 5, which is defined by a wall 28 of the retainer body 12. A portionof the wall 28 has an arcuate shape defining a substantiallysemicircular opening 30 of the recess 26. The opening 30 hassubstantially the same diameter as the main body section 56 of the bolt52. A further portion of the wall 28 defines an entrance 32 of therecess 26 which extends from the front face 18 and opens into thesemicircular opening 30. The wall 28 further includes rounded surfaces34 located between the portions of the wall 28 defining the entrance 32and the semicircular opening 30. The rounded surfaces 34 are spacedapart a distance slightly narrower than the main body section 56 of thebolt 52 to form a constriction at the entrance of the semicircularopening 30. The constriction serves to capture the main body section 56of the bolt 52, thereby releasably retaining the bolt 52 within thechannel 22.

A method for mounting the heat shield 60 onto the polymeric fuel tank 40by employing at least one heat shield retainer 10 will now be described.It is first noted, that it is within the skill of one working in the artto make a determination of the required number of heat shield retainersneeded to mount a given heat shield having a certain shape and weight.

The retainer body 12 of each required heat shield retainer 10 is securedonto the polymeric fuel tank 40 just after the tank has been formed andbefore it has cooled. Each retainer body 12 is secured onto the fueltank 40 by inserting its respective bulbous pegs 21 into correspondingsockets 43 formed within the fuel tank 40. As the tank 40 cools, thepolymeric material of the fuel tank 40 defining the sockets 43 willcontract around the pegs 12. As a result, after the tank cools, the pegs21 are locked within the sockets 43, and hence to the fuel tank 40.

After the heat shield retainer bodies 12 have been mounted onto the fueltank 40, bolts 52 are snap-fitted into the channels 22 of the retainerbodies 12. The heat shield 60 is subsequently placed on the retainerbodies 12. As the heat shield 60 is placed on the retainer bodies 12,the main body section 56 of each bolt 52 extends through a correspondingopening in the heat shield 60. Thereafter, nuts 54 are threadedlyengaged and tightened onto the bolts 52, thereby securing the heatshield 60 onto the heat shield retainers 10, and hence the fuel tank 40.

Having thus described the heat shield retainer and a method foremploying the same to mount a heat shield onto a fuel tank of thepresent invention in detail and by reference to a preferred embodimentthereof, it will be apparent that modifications and variations arepossible without departing from the scope of the invention defined inthe appended claims. For example, it is contemplated that one or anynumber of pegs could be utilized on the retainer of this invention.Further, it is contemplated that the retainer of the present inventionmay be employed to secure together elements other than a fuel tank and aheat shield.

What is claimed is:
 1. A method for forming a fuel tank assembly comprising the steps of:forming a fuel tank having at least one socket therein from heated polymeric material; providing a heat shield; providing retainer means for connecting said heat shield to said fuel tank, said retainer means including a retainer body having peg fastening means on a first side thereof for connecting said retainer body to said fuel tank; connecting said retainer body to said fuel tank by inserting said peg fastening means into said at least one socket in said fuel tank after said tank has been formed and before said tank has cooled in order to permit said socket to contract about said peg fastening means as said tank cools; and attaching said heat shield to said retainer body.
 2. The method for forming a fuel tank assembly as set forth in claim 1, wherein said retainer means further includes a channel located on said retainer body and a bolt and nut combination; andwherein said step of attaching said heat shield to said retainer body comprises the steps of: snap-fitting said bolt in said channel located in said retainer body; placing said heat shield on said retainer body; and fastening said heat shield onto said retainer body by threadedly engaging and tightening said nut on said bolt.
 3. A method for forming a fuel tank assembly, said method comprising the steps of:forming a fuel tank from heated polymeric material; forming at least one socket in said fuel tank; providing retainer means for retaining an object on said fuel tank, said retainer means including a retainer body having fastening means thereon for connecting said retainer body to said fuel tank; connecting said retainer body to said fuel tank by inserting said fastening means into said at least one socket in said fuel tank after said tank has been formed and before said tank has cooled in order to permit said at least one socket to contract about said fastening means as said tank cools.
 4. A method for forming a fuel tank assembly as set forth in claim 2, wherein said retainer body and said fastening means are formed integrally with one another.
 5. A method for forming a fuel tank assembly as set forth in claim 3, further comprising the step of attaching a heat shield to said retainer body.
 6. A method for forming a fuel tank assembly as set forth in claim 3, wherein said fuel tank is formed with two sockets therein.
 7. A method for forming a fuel tank assembly, said method comprising the steps of:forming a fuel tank from heated polymeric material; forming at least one socket in said fuel tank; providing retainer means for retaining an object on said fuel tank, said retainer means including a retainer body having peg fastening means thereon for connecting said retainer body to said fuel tank; connecting said retainer body to said fuel tank by inserting said peg fastening means into said at least one socket in said fuel tank after said tank has been formed and before said tank has cooled in order to permit said at least one socket to contract about said peg fastening means as said tank cools.
 8. A method for forming a fuel tank assembly, said method comprising the steps of:forming a fuel tank from heated polymeric material; forming at least one socket in said fuel tank; providing retainer means for retaining an object on said fuel tank, said retainer means including a retainer body having fastening means thereon for connecting said retainer body to said fuel tank, a channel located in said retainer body and a bolt and nut combination; connecting said retainer body to said fuel tank by inserting said fastening means into said at least one socket in said fuel tank; snap-fitting said bolt in said channel located in said retainer body; placing a heat shield on said retainer body; and fastening said heat shield onto said retainer body by threadedly engaging and tightening said nut on said bolt.
 9. A method for forming a fuel tank assembly, said method comprising the steps of:forming a fuel tank from heated polymeric material; forming at least one socket in said fuel tank; providing retainer means for connecting an object to said fuel tank, said retainer means including a retainer body having fastening means for connecting said retainer body to said fuel tank; and connecting said retainer body to said fuel tank by inserting said fastening means into said at least one socket in said fuel tank after said tank has been formed and before said tank has cooled in order to permit said at least one socket to contract about said fastening means as said tank cools.
 10. A method for forming a fuel tank assembly as set forth in claim 9, wherein said fastening means comprises peg fastening means for connecting said retainer body to said fuel tank.
 11. A method for forming a fuel tank assembly as set forth in claim 9, further comprising the step of attaching a heat shield to said retainer body.
 12. A method for forming a fuel tank assembly as set forth in claim 11, wherein said retainer means further includes a channel located in said retainer body and a bolt and nut combination; andwherein said step of attaching said heat shield to said retainer body comprises the steps of: snap-fitting said bolt in said channel located in said retainer body; placing said heat shield on said retainer body; and fastening said heat shield onto said retainer body by threadedly engaging and tightening said nut on said bolt. 